Doesn't quite meet the first criterion, but Wes Boyd's Magic Carpet has a main character who pays her way through college by working in a Nevada house; some others of his works also touch on this or a similar theme.

Part of that was to establish that 1) yes, it actually was a central theme of the novel, and 2) that the protagonist is genuinely that into it. This has to be established early on for one of the central themes of the novel, and pretty near all future mention of her in his other stories, to hang together.

it pops up numerous times throughout the story, and is a key element in a later sub-plot but it's not a core plot element so it only accounts for a small portion of what happens in the story while also helping to push parts of the story.

If you're talking about descriptions of sex, then Wes' stories probably won't suit you; they're either No Sex or Minimal Sex, though Magic Carpet has about the highest sex content; although he tells you what a 'one hour, two pop half-and-half' is, he doesn't describe the (sex) action. I'm re-reading it again (having started at the top of this thread interrupting my reread of all his stories), and Jennlynn has just had a dogfight with a fighter ace with a $12000 night in bed double-or-nothing bet riding on it.

Thinking Horndog'sStrange Relationships has a little about setting up a high-class prostitution business towards the end of the story, but the story ends before it gets set up; this is a Much Sex story, with plenty of descriptions, set in the Second Best universe.

This is another of Thinking Horndog's sex driven stories. There is some MM/cuckold action, if that's a squick for you, you might want to skip this one.

It's the story of how a nice guy winds up with a dozen or so women, most of them working girls (sex for cash work), two he buys because they are pregnant and of almost no value to their pimp, and the rest sort of accumulate as events progress. There is making a pornographic film in the plot and at the end "she's pregnant" reflects the opening line, but this time the hero is the father.

I think you will like the hero and some of his friends and associates, who seem like real people to me. This story doesn't strain the 50 ton crane I use to suspend disbelief.

It's a good plot with action and believable characters, no technical issues and as a lot of this author's stories do, appeals to me as a ten. I am glad to say it is not the best story he has written, but it is very good and I can't review some of the even better ones because some other reviewer beat me to them. He has written more than 40 stories. Go read some of them. I am pretty sure you will be glad you did.

it pops up numerous times throughout the story, and is a key element in a later sub-plot but it's not a core plot element so it only accounts for a small portion of what happens in the story while also helping to push parts of the story.

OK, thanks... Maybe later then. I'd prefer it to be the main plot.

Thinking Horndog's Strange Relationships has a little about setting up a high-class prostitution business towards the end of the story, but the story ends before it gets set up; this is a Much Sex story, with plenty of descriptions, set in the Second Best universe.